Electronic equipment using semiconductor device are essential for many modern applications. With the advancement of electronic technology, electronic equipment is becoming increasingly smaller in size while having greater functionality and greater amounts of integrated circuitry. Thus, the semiconductor device inside the electronic equipment is also becoming denser, smaller and more compact. The continuous demands for a size reduction of semiconductor device has made it necessary to develop more integrated circuits that can be accommodated within the semiconductor devices.
The major trend in the electronic industry is to make the semiconductor device smaller and more multifunctional. The semiconductor device comprises an electrical interconnection structure for electrically connecting a number of metallic structures between adjacent layers of the semiconductor device so as to minimize the final size of the semiconductor device as well as the electronic equipment. In a field of microelectronics as well as three dimensional wafer level integration, a technology of wafer bonding is applied to support the dense and multifunctional semiconductor device. The semiconductor device includes two or more wafers which are bonded together by different principles such as direct bonding or interlayer bonding.
Numerous manufacturing operations are implemented within such a small and high performance semiconductor device. Thus, manufacturing the semiconductor device in a miniaturized scale becomes more complicated. An increase in a complexity of manufacturing the semiconductor device may cause deficiencies such as poor coplanarity of bonded wafers, inaccurate wafer bonding, poor reliability of the electrical interconnection, and development of cracks within components. Thus, there is a continuous need to improve the method for manufacturing the semiconductor device in order to solve the above deficiencies.